1. Field of the Invention
The present invention relates to a chip antenna for terrestrial digital multimedia broadcasting (DMB), and particularly to a chip antenna for terrestrial DMB, which is minimized to a chip-shape antenna by an LTCC (Low Temperature Cofired Ceramics) process and realizes a widened bandwidth using various dissipative structures of current distribution, so that the antenna can be stored in a personal digital assistant (PDA) and can provide a wide band adequate for receiving the terrestrial DMB.
2. Description of the Related Art
Generally, the term “digital multimedia broadcasting (DMB)” means a broadcasting system, which can transmit characters, graphics, moving images as well as voice data having a high, compact disk-quality level, without being limited to simple audio services, such as the existing AM broadcasting or FM broadcasting. Typically, although the DMB indicates a terrestrial broadcasting system, which offers free services on the air in a local area, broadly speaking, it comprises satellite digital audio broadcasting (DAG), which offers fee-based services on the air, concurrently using a space system and a ground network.
Moreover, the DMB is an audio broadcasting system completely different from the existing analog voice processing system and the existing modulation system. Specifically, as for a main broadcasting system, the DMB adopts a digital voice processing system and a digital modulation system having a strong point in noise or deterioration as a modulation system. As the voice processing system, the DMB adopts an audio compression system of MPEG I Layer 2, which compresses a huge amount of data to be suitable for sending and storing, and as the modulation system, it adopts a COFDM (Corded Orthogonal Frequency Division Multiplexing) system, which is excellent in moving object receiver capability.
The DBM has an usable frequency of about 174˜240 MHz in a band-III and of about 1,452˜1,492 MHz in a band-L. Thus, for instance, when realizing a λ/4 antenna of 200 MHz, the antenna must have a straight line length of about 37 cm (1.5M/4).
A conventional antenna for the terrestrial DMB is shown in FIG. 1.
FIG. 1 is a diagram illustrating an appearance of the conventional chip antenna for the terrestrial DMB. The conventional chip antenna for the terrestrial DMB shown in FIG. 1 is an antenna enabling analog/digital television broadcasting in a VHF/UHF bandwidth to be watched in a vehicle or room. Referring to FIG. 1, the conventional chip antenna for the terrestrial DMB has a structure modified from a ½-wavelength dipole antenna, in which a radiator of the dipole antenna is formed of a strip line and folded to make creases in a zigzag, thereby realizing miniaturization of the antenna and a wide bandwidth.
Nevertheless, in view of the fact that the manufactured antenna in practice has a length of about 44 cm, the conventional antenna has a problem in that the antenna is too large to be stored in the PDA or a DMB terminal.
Additionally, since the minimization of the antenna causes a problem of a narrowed band, it is necessary to overcome the problem of the narrowed band caused by the minimized antenna.